This invention is directed to a primer composition and in particular to primer composition that can be used to repair automobiles or trucks at the end of a production line.
Primer compositions are well known in the art and are widely used in painting of automobile and trucks in both the production process and in repair of automotive and truck finishes. Thermosetting polyester resins and coating compositions of these resins are shown in Tobias et al. U.S. Pat. No. 4,238,583 issued Dec. 9, 1980 and Lasher U.S. Pat. No. 4,071,578 issued Jan. 31, 1978. A sealerless primer is shown in Simon U.S. Pat. No. 4,232,090 issued Nov. 4, 1980. However, none of these compositions provide a high quality primer that has excellent adhesion to all types of painted, primed and unprimed substrates. Such a primer is needed for an end of the line repair primer.
In a typical manufacturing facility, after the automobile or truck has been assembled and painted, often there are small scratches, dents and other imperfections in the finish that need to be repaired. The finish may need to be sanded and primed or may not require sanding. Any primer used, must have adhesion to all types of substrates. The primer must adhere to the top coat which may be a pigment top coat or may be a clear over a pigment top coat or to the primer layer or to a bare metal or plastic substrate. Conventional primers do not have excellent adhesion to all of these substrates and there is a need for an improved primer. composition that has such excellent adhesion.